Thames Water customers have been told they will pay for the £3.6bn scheme through an annual rates increase of more than £10 a month. Bills are not expected to fall back to their current levels once construction work is complete.

Councillors fear the hike could be even more severe if the project runs over budget.

Cllr Govindia has written to Environment Minister Peter Benyon calling for a limit to be imposed on the amount Thames Water’s customers will have to pay towards the scheme.

He said:
“Households in London have been told the super sewer will cost them around £60 a year. Our fear is this figure will rocket if the project runs into trouble.

“We know from bitter experience that the cost of major infrastructure projects can far exceed the estimates presented at the planning stage – the Jubilee Line extension and Channel Tunnel are memorable examples.

He continued:
“What concerns us about the super sewer is that Thames Water could simply pass rising costs on to their customers. As the region’s sole water and sewer provider there would be no escape for our residents.

“Imposing a cap on these increases is the only sure way to protect Londoners from further hardship at a time when they are already struggling with recent hikes in the cost of gas, electricity, food, petrol and public transport.”

Wandsworth Council supports the objective of the ‘super sewer’ project – reducing the amount of sewage flowing into the river – but has consistently voiced concerns over the scheme’s costs and the environmental impacts on the construction process.

The council is a member of the Save Barn Elms Alliance - a coalition of campaigners fighting to save a valuable playing field from being used as one of the main tunneling compounds during the super sewer’s seven year construction programme.

Thames Water has identified an alternative brownfield location where these works could take place. Unlike greenfield Barn Elms this is a semi-derelict industrial site with no trees, no grassland, no sports pitches, no riverside towpath and no wildlife habitats to disturb.

A final decision on which of these sites will be used has not yet been made and the Save Barn Elms Alliance has pledged to continue its campaign until the playing fields are declared safe.

The coalition's full membership includes residents' pressure group Stop the Shaft, Wandsworth and Richmond Councils, local MPs Justine Greening and Zac Goldsmith, GLA members Richard Tracey and Tony Arbour, The Putney Society and The Barnes Community Association.

The Alliance is not opposed to the 'super sewer' project as a whole, only the use of this unspoilt beauty spot as the main tunnelling site.